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A252071
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Number of (n+2)X(4+2) 0..2 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 3 or 4
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1
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375, 1135, 5085, 21862, 92225, 391934, 1669294, 7114867, 30309042, 129016031, 549319037, 2339547000, 9963141845, 42425232250, 180661430026, 769335984173, 3276146397838, 13951092432179, 59409215103993, 252988054381898
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OFFSET
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1,1
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COMMENTS
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LINKS
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FORMULA
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Empirical: a(n) = 2*a(n-1) +5*a(n-2) +14*a(n-3) +34*a(n-4) -16*a(n-5) -79*a(n-6) -150*a(n-7) -94*a(n-8) +581*a(n-9) +457*a(n-10) -913*a(n-11) -631*a(n-12) +692*a(n-13) +433*a(n-14) -236*a(n-15) -116*a(n-16) +72*a(n-17) -57*a(n-18) -32*a(n-19) +38*a(n-20) -15*a(n-21) +5*a(n-22) +11*a(n-23) -4*a(n-24) for n>26
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EXAMPLE
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Some solutions for n=4
..2..1..2..2..1..2....2..2..2..2..1..2....1..2..2..2..2..1....2..2..2..2..2..2
..1..2..2..2..2..1....2..2..2..2..2..2....2..2..2..2..2..2....2..2..2..1..2..2
..2..2..2..2..2..2....2..1..2..2..2..2....2..2..2..2..2..2....2..1..2..2..2..2
..2..1..2..2..2..2....2..2..2..1..2..2....1..2..2..2..2..2....2..2..2..2..2..2
..2..2..2..2..2..1....2..2..2..2..2..2....2..2..2..2..2..1....1..2..2..2..2..2
..2..2..2..2..2..2....1..2..2..2..1..2....2..2..2..1..2..2....2..2..2..2..2..1
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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